Midterm elections this week are poised to set off a political game of musical chairs on Capitol Hill that could have significant impacts on defense issues ranging from topline spending to Ukrainian military aid to U.S. shipbuilding. The prevailing narrative, according to polls and political analysts, is that Republicans are set to make key midterm election gains that are likely to lead to a new majority in the House and, possibly, the Senate. Analysts say understanding potential leadership and membership...